The strike occurred overnight Thursday into Friday, the officials told the AP. It did not appear that a chemical weapons site was targeted, they said, and one official said the strike appeared to have hit a warehouse.

The U.S. officials spoke on condition of anonymity because they were not authorized to discuss the matter publicly.

Israel has targeted weapons in the past that it believes are being delivered to the Lebanon-based militant group Hezbollah. This week, Hezbollah leader Sheikh Hassan Nasrallah said his group would assist Syrian President Bashar Assad if needed in the effort to put down a 2-year-old uprising.

Israeli Embassy spokesman Aaron Sagui would not comment Friday night specifically on the report of an Israeli strike into Syria.

"What we can say is that Israel is determined to prevent the transfer of chemical weapons or other game-changing weaponry by the Syrian regime to terrorists, specially to Hezbollah in Lebanon," Sagui said in an email to the AP.

In 2007, Israeli jets bombed a suspected nuclear reactor site along the Euphrates River in northeastern Syria, an attack that embarrassed and jolted the Assad regime and led to a buildup of the Syrian air defense system. Russia provided the hardware for the defense systems upgrade and continues to be a reliable supplier of military equipment to the Assad regime.

The airstrike, first reported by CNN, came hours before President Barack Obama told reporters at a news conference in Costa Rica on Friday that he didn't foresee a scenario in which the United States would send troops to Syria. More than 70,000 peoples have died and hundreds of thousands have fled the country as the Assad regime has battled rebels.

Obama said ground troops were not among the options being considered as his administration seeks to bolster rebel forces.